Philippe de la,** a distinguished French geometer of the seventeenth and eighteenth centuries, was born in Paris in 1640. His father, Laurent de la Hire, was a painter and engraver of considerable note, and the son's education was at first shaped so as to fit him for the same career. In his twentieth year La Hire made a pilgrimage into Italy, and while at Venice fell in with the Comic Sections of Apollonius, which determined his taste for mathematical study. His own treatise on this subject, published in 1685, under the title of *Sections Coniques in Novem Libros Distributa*, is the most important of all his works. In 1678 he was admitted into the Academy of Sciences, and was afterwards appointed by Colbert to assist Picard in conducting the surveys for a general map of France. A few years later it devolved upon him to continue, along with Cassini, the measurements of the meridian begun by Picard in 1669, and the work was progressing happily till stopped by the untimely death of Colbert. He was subsequently employed on a great number of public works, of which the most important were connected with the supply of water to Versailles and Paris. "France might have had in La Hire," says Fontenelle, "an entire Academy of Sciences." He was a quiet man, of great practical prudence, very reserved in manner, and of the most spotless integrity of personal character. His piety was as much admired by his friends as his probity. He was twice married, and two of his sons were admitted into the Academy of Sciences, the one on the score of his geometrical, the other of his botanical knowledge. La Hire died suddenly in 1718. His principal works are—

* Nouvelle Méthode de Géométrie pour les Sections des Superficies Coniques et Cyclindriques*, Paris, 1673, in 4to; *De Cycloide Opusculum*, ibid., 1676, in 4to; *Nouveaux Éléments des Sections Coniques*, *les Lignes Géométriques, la construction ou affection des Equations*, ibid., 1679, in 12mo; *La Géométrie, ou le traité de tracer des cadres*, ibid., 1682, in 12mo; *Sections Coniques, in ix. libris distributor*, ibid., 1685, in folio; *Tabula Astronomica*, Ludovici Magni jusu et manifestissima exarata*, ibid., 1702, in 4to; *L'Ecole des Arpentiers, avec un Abrégé du Nivellement*, ibid., 1689, in 8vo; *Traité de Mécanique, où l'on explique tout ce qui est nécessaire dans la pratique des Arts*, ibid., 1675, in 12mo; besides a great number of *Mémoires*, different journals, and in the Collection of the Academy. La Hire also was editor of the *Traité du Nivellement* by Picard; of the *Traité du Mouvement des Eaux* by Mariotte, and joint editor with Bolvin and Thévenot of the *Veteres Mathematici Graec. et Latini*, 1683.

**HIRPINI,** an inland people of Italy who inhabited the southern portion of Samnium. They are sometimes regarded as merely a Samnite tribe, by others they are looked upon as an independent nation. The country they inhabited was the wild and mountainous district traversed by the Sabatia, Calor, and Tamarus, tributaries of the Vulturinus, and on the eastern side of the Apennine ridge, the upper course of the Aufidus. In the early history of Rome the Hirpinii are found identifying themselves with their Samnite neighbours against their common foes. They seem to have been subdued in the early part of the third century B.C., as in 268 B.C. Beneventum, the key of all their military positions, was colonized by Roman settlers. In the second Punic War the Hirpinii appear in history for the first time as an independent people. Revolting from their old conquerors, they joined the Carthaginian invaders, and though they were unable to recapture their stronghold of Beneventum, they remained faithful to Hannibal till the defeat at the Metaurus restored the empire of Italy to his opponents. In the year of that event the Hirpinii made their peace with their old masters by betraying into their hands the garrisons of their allies. From this time till the outbreak of the Social War, the Hirpinii seemed to have continued steadfast in their allegiance. On that occasion, however, they set the example of revolt to the allies, and might have become formidable enemies, had not the rapid successes of Sulla induced them to repair their error by a complete submission. At the close of this war the Hirpinii obtained the franchise, and do not again appear in history as an independent people. Their chief towns were Beneventum, Æculanum, Trivicum, Equus Túticus, Murgantia, and Aquilonia. The most important of these are given under their respective heads.

**HIRSCHBERG,** a fortified town of Prussian Silesia, capital of a cognominial circle in the government of Liegnitz, and 25 miles S.W. of the town of that name, on the River Baber. It is the seat of the superior courts for the circle, and a great emporium for linen manufactures and hosiery. In the town and neighbourhood are bleaching works, paper-mills, and sugar-refineries; and not far off is the celebrated watering-place of Warmbrunn. Pop. 7654.

**HISPANIA.** See Spain.

**HISSAR,** a town of Hindustan, and the principal place of a Pergunnah, situated in the British district of Hurreecanah, within the jurisdiction of the lieutenant-governor of the N.W. provinces. The country is fertile, but labours under a scarcity of water, which detracts from its fertility. It is only watered by one small stream, namely, the Sursufty. In order to supply the means of irrigation, one of the Afghan emperors, who lived in the fourteenth century, caused two canals to be cut, one from the Sutej, and the other from the Jumna, both of which joined at the city of Hissar, whence they are supposed to have been divided into a number of branches, so that the water was nearly all distributed over the lands, and the remainder fell into a lake called Bhedar. Under the influence of this extensive irrigation the country became fertile, and yielded two abundant crops in the year. These canals were suffered to fall to decay, but in 1825 the branch from the Jumna was cleared out by order of the British government as far as Darbah, 25 miles N.W. of Hissar, to which place it is navigable for timber rafts. The neighbouring country produces horses, camels, and cattle. The inhabitants are chiefly Jauts, with the exception of a few Rajpoots; there are also villages of Rajpoots who have embraced the Mohammedan religion. This district imports matchlocks, swords, coarse white cloth, salt, sugar, and a small quantity of rice and spices. The exports are horses, camels, bullocks, and ghee. During the prosperity of the Mogul government the town and district were considered the personal estate of the heir-apparent to the throne. Hisar was built by Sultan Feroz, who gave previous directions for the digging of the two canals above mentioned; after which he laid the foundations of the town and fortress, which he built of stone brought from the neighbouring hills of Nosa, and completed it in less than three years. E. Long, 75. 50., N. Lat. 29. 8. (E.T.)